BASH: Send email via curl command (gmail example)

curl smtps://smtp.gmail.com:465 -v --ssl --mail-from "SENDER@gmail.com" --mail-rcpt "RECIPIENT@gmail.com" --user SENDER@gmail.com:SENDER_PASSWORD --upload-file /tmp/mail.txt


* For gmail accounts, must enable access for less secure apps at https://security.google.com/settings/security/activity.



[user@computer tmp]$ cat mail.txt
From: "User Name" <username@gmail.com>
To: "John Smith" <john@example.com>
Subject: This is a test

Hi John,
I'm sending this